Circular electric lamp



Jan. 2, 1945.

W. J. GEIGER CIRCULAR ELECTRIC LAMP Filed Oct. 18, 1941 lnvenfor' Wal'fer J. Gel

gar, m mm His 'A'f'kor'neg. I

same cathode mounts as for straight tubes.

UNITED GIR'CUIAB, ELECTRIC LAMP Walter J. Geiger, Cleveland Heights, Ohio, as-

signor to General Electric Company, a coir-pm ration of New York Application October 18, 1941, Serial. No. 415,597

11 Claims.

This invention relates to lamp of a type comprising long envelopes formed in a bent and more or less nearly closed configuration-a tubular vitreous envelope bent to a circular outline being a representative and very desirable form. For convenience, the general type of lamp here involved may be generically referred to as circular, though it is to be understood that this invention naturally includes lamps whose tubula-r envelopes are bent to polygonal, oval, or other closed configurations. While the means of trans lation employed in such. a circular lamp for comverting electrical energy into useiul radiation may be of any kind desired, electrical discharge means are particularly suitable, and especially fluorescent tubes of the usual positive column type. For domestic lighting, a circular fluores cent lamp is very'generally more desirablethan the long, straight tubes now in common use; e. g., its relative compactness adapts it for installation under the shades of ordinary table lamps and floor lamps, where even low wattage straight tubular lamps would be impracticable. The advantage will readilyv be appreciated when it is considered that a. 30-watt fluorescent tube 36 inches along makes a circular lamp such as here illus trated having an over-all diameter of only about 12% inches. 1

Instead of attempting to fabricate an endless tube forming a closed figure or circle, it is preferred to construct the lamp with a tubular envelope having closed ends and curved or bent in a suitable closed configuration, so that these ends lie adjacent and more or less nearly opposite one another. This allows the current connections for the translation means in the tube to be brought out to its exterior at the ends of the tube, and preferably through its end walls. It also allows of constructing and scaling in the tube ends very much as in the manufacture of ordinary straight fluorescent tubes, using the Indeed. it is even possible to virtually complete the manufacture of the fluorescent lamp as a straight tube, only heating and bending it to the desired final configuration just before exhaust, charg ing with working substance and starting gas, and sealing oil, etc. Methods of bending that may be used for this purpose are described in United States Patents No. 1,534,685, April 21, 1925, Claude and de Beaufort, and No. 2.080599, May 18, 19-37, Pirani and Fehse. Prior to exhaust oi the fluorescent tube. air may be blown into it dur ing bending through smexhaust tubulature form ing part of one of its cathode mounts; and if bending operat appearance; adaptability o the lamp envelope,

r so. ately basing; H with bases such as commonly i e fluorescent tubes, I provide a commie base ture for the juxtaposed envelope M with contact terminals for oonnec on current connections or leads. These contact minals may be arranged for access sidewise the base and of the circular prefe from the inner side of the lamp tube ctr l common base structure the gap between the enve the current lease of th out of the envelope and are or tact terminals, and may irrte cnl surround the envelope ends themselves. the base may completely close the figure the lamp.

The stricture disclosed and c 415,594, Ward 1 Patent No. J

In accordance with my en provide ilor mounting star g other accessories, if desired the for the juxtaposed tube ends. this new arrangement of the starting SW1 ch, have devised a novel type and form of base c taut advantages -suoh as tion, involving only a few ture and assembly of the cation of the base to a la the starting switch or oth base, when resuired: corn accommodate wide 'variatic between the tube ends, and. variations in the angels" Various other featnr invention will appear i1" tier: of species forms the drawing.

In the drawing, Fig. tive of a siren; lug my invention; Fig. J view of lamp portion. of the envelope midwection; and Fig. 3 of the parts of the base.

In 1 am there umn fluorescent lamp true axial n technical the envelope in r nearly the pproaches 360. the ends .1 i, ll comprise it, it, of glass stern as usual, these ends Wt reduced in size at I3, or leads H, H for i2, 12 extend olcpo ill at its end H, mounts l2, l2, which 'lvelcpe. An internal ewallgis indicated :ry is indicated by a in will also at osphere of starting of several millicf e:

Anion to the ad wn in Figs. 1, 2, plurality of contact terto he current leads H. "LIifidfiilfi 2! are acso and of the circular "ated by the position of 1c pins in Fig. 1, and

shown with an around the conhollow to engage f the lamp ll, as exr s 20 comprises an inner sides of the adjacent o ter part in the i that engages sides a; .ne envelope ends and i dctaehably sea molded pcr ll and sheet tonal for outer part tube circle ll, carries the i, 2| at its own inner side, we as a housing for lamp a starting switch The parts 25, 25 may A as ends ll, H, and may soldered to all the leads.

ting character (transparent or translucent) to let the light from the lamp ends H, H or from the glow switch 35 shine through, the liner 32 being omitted or made transparent or translucent. The margins of the cover part 28 that overlap the edges of the part 25 may be secured thereto by fasteners 28, 38 such as screw bolts taking through the ends of the part 25 and of the cover 26. As here shown, the cover 26 is provided with a flexible insulative liner 29, of fiber or asbestos, for example, that surrounds or envelops the parts between the tube ends H, and even overlaps the latter.

As shown in Figs. 2 and 3, the ends of the part 25 that engage against the inner sides of the circular envelope end H, H are hollowed about axes approximately coincident with the axes of the tubular envelope ends so as to seat properly on the envelope ends; but these hollowed seating surfaces 43, ll of this part 25 diverge inward irom the tube ends. Similarly, the sheet metal of the cover 26 is embossed outward between its end edges that engage and fit against the outer sides of the tube ends H, H, in such a way as to diverge outward from the tube ends. This enlargement inward of the hollow of the base 20 with respect to its end openings that accommodate or engage around the tube ends I I, ll takes care of a considerable range of variation in the angular relation of these adjacent tube ends in diflerent lamps; while the length of the base 20 axially of the tube ends takes care of considerable variation of the distance apart of these ends. As shown in Figs. 2 and 3, the holes N, N in the part 25 for the fasteners 28, 38 are elongated crosswise. of the tube ends H, H to allow adjustment of the part 25, 25 relative to one another to take care of variations of size or of relative direction of the tube ends.

As shown in Figs. 1, 2, and 3, two of the current connections or leads H, H of the cathodes in the tube ends H, H are connected to the contact terminals 2|, 2|. These contact terminals 2|, 2| are hollow posts or pins molded into the wall of plastic at the bottom of the recess :1, and thus extending into the interior of the base 20, and the leads H, N are brought down through them and soldered fast in them, thus holding the part 25 to the tube ends H, II (as shown in Fig. 2) before the cover 26 is put on. The contact terminals 2|, 2| may be connected across an a. 0. power line P through the usual control switch 8 and choke coil C, which may also serve as a starting inductance, all as diagrammatically indicated in Fig, 2. The other two current connections 01" leads H, H are shown as connected together through the starting glow-switch 35, in parallel with the condenser 38, these parts 25, 86 being conveniently placed in the hollow part 25 and connected as described after the contact tenninals 2 l, 2| have been connected to the other leads M, H. For this purpose, a connector device or structure is shown in the space between the tube ends H, H at the side thereof adjacent the cover part 26, consisting of an insulating disc with hollow connector posts 4|, 4| upstanding .ierefrom at its outer side and provided with peripherally grooved heads 42, 42, which are readily accessible when the cover 28 is removed, 3. After the parts 35, 36 have been put in place, the connector 40 may be placed over them with their leads extending up through the posts If, 4|, and then the proper leads H, I may be wrapped around the heads 42, 42, and the latter It then only remains to ascents I place the cover 28 with its insulative liner 3! around the tube ends and the parts between them, and secure the corners of its overlapping margins to the edges of the part 25 by the fastener bolts 38, 3E,

As shown in the drawing, the base structure 25, 2G encloses only a short length of each end of the envelope so that it constitutes but a minor portion oi the peripheral surface of the closed configuration. v

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An electric lamp comprising a tubular vitreous envelope having electric energy translation means therein, for converting electric energy into radiation, and formed to a bent substantially closed configuration, with its ends adjacent and directed toward one another, and having current connections for said translation means extending to its extcriorat its ends; a common base for the adjacent envelope ends provided with contact terminals for connection to their said current connections; and automatic starting switch means in said base for controlling the connection of the aforesaid current connections to said contact terminals.

2. An electric lamp comprising a tubular vit' reous envelope having electric energy translation means therein, for converting electric energy 3. An electric lamp comprising a tubular vitreous envelope having electric energy translation means therein, for converting electric energy into radiation, and formed to a bent substan tially closed configuration, with its ends adjacent and directed toward one another, and havin current connections for said translation means extending to its exterior at its ends: a common hollow base around the adjacent envelope ends provided'with contact terminals accessible, for connection, sidewise thereof, and also having an internal recess; and automatic starting switch means in said recess for controlling the connection of the aforesaid current connections to said contact terminals.

4. An electric lamp comprising a tubular vitrcous envelope having electric energy translation means therein, for converting electric energy into radiation, and formed to a bent substantially closed configuration, with its ends adjacent and directed toward one another, and having current connections for said translation means extending to its exterior at its ends; a common base for the opposed envelope ends comprising hollow parts lying at the sides of said envelope ends and open to the space between said ends, and ooeteucl'lobi}, secured together, contact terminals for connection to the aforesaid current connections mount ed on one of said base parts; and automatic start ing switch means accommodated in one of said. base parts, for controlling the connection of the aforesaid current connections to said contact terminals.

.5, An electric lamp comprising a tubular vitre ous envelope having else means therein, for c into radiation, and in tially closed conilgurat and directed t ward rent connect on tending to the opposed envelope e them; a part c close in said space, terminals connected both envelope ends; 2: in said hollow part cor connections of said ER! in 6. An electric lamp 6 ous envelope having e ect: means therein, ior into radiation, tially closed configu cent and directed to ins; current cnnec moons exterior hollow opposed e peem tween said ends, and minsls at its own lr said current connector:

extending arou envelope ends and the having its margins s: and enters "c start" termini-t I Z.. An loll ous envelope havin means therein, :for

to its ex r lying at inner slow connected to both. envelope extending around the outer sides of on ends and the space between them, coasting provided with insulative connected to other o envelope ends; and an condenser means in s nected in parallel to t e. An electric isms one envelope having cent and d current conic cotter.

i town" o he or lit sides of anterior oi -d .0 said curlu said shell enos i sold enve -.lucture enclosing only a ,1 end of. 3 envelope so that t a minor portion oi the periphface of the closed configuration.

An electric lamp comprising a tubular enhent to a substantially closed circular configuration with its ends directed toward each other and having lead-in conductors extending outwardly from said ends into the space therebetween, and a base structure comprising a block snide-n61 openmember of insulating material bridging the gap '"itions in the between said ends of the envelope and carrying slope said contact members at its exterior, and a longitudiof each end of nally split shell of sheet material surrounding the out 9. minor 20 said ends of the envelope and the space thereof the closed between to complete the closed configuration of the lamp, means clamping said block member and shell together and to the ends of the envelope, th said leacl-in conductors being electrically contoward each 25 nected to said Contact members through the intema ial between the ii at lcto extending rior of the shell, the said base structure enclosing a u 1 star i, comprising a only ashort length of each end of the envelope so sheet material surthat it constitutes but a minor portion of the e e velop and the space peripheral surface of the closed configuration.

' r closed configura- :0

. ieznber of insulating WALTER J. GEIGER. 

